Can you repeat this problem in different breaking zones or was this problem occuring at one breaking zone on one track in particular? Maybe there was a cross slope causing the car to drift to one side. Just a thought.

 

It happens in any straight braking zone. It just has to be a hard brake from over 100+ mph. If I reduce the braking effort the pulling goes away. I suspect if I tried a full brake from 100+ mph on OEM pads that I would not feel the pulling, but haven't really experimented with it.

I'll inspect the front suspension mounts. I guess it is about time that stuff starts to break on the car. The lap times are coming close to be competitive at our club level. Starting to crack front rotors and feel the Torsen LSD act up in high speed sweepers too.

 

Fongu,

Is this happening at Shannonville?

 

does very little unless the car's flat bottomed

 

Like I've said, I've been experiencing this for any 100+ mph hard braking zone with the RA1's and race pads. Up until now I just laid off on the braking in these situations, but now it cannot be ignored to get faster. It's not unmangeable, but it makes it more difficult to control the line.

Had the same kind of pulling at Shannonville (end of Fabi straight), Calabogie (end of Rocky Road) and Watkins Glen (I think it's into turn 1).

The aero explanation makes sense because of the speed dependency. I also think that the aggressive bite of the VR2 might be too much for the "low grip" of the RA1's causing the initial brake imbalance. Suspect that by either going to sticker tires or one step lower in brake pad aggressiveness will help the problem too. I'm getting close to replacing the front pads and rotors, so I'm looking to get input before deciding on what to replace them with.

 

Steve, is ABS engaging? Maybe there is a problem with one of the wheel sensors but it is not throwing a code. Give the ABS wires a check when you look at the A-arms. I am just thinking out loud here...

 

an aero imbalance shouldn't be the culprit of throwing a car to one direction; since this is a case of initial brake application, therefore the car should be just in the longitudinal direction.

I'd suspect suspension components as well, since the load that the fronts see should be pretty big given the weight of the car and the forces induced due to the long g at that given moment.

I'd look at the A-arms AND the tie rods thoroughly before going on a witch hunt for something else. If the fronts toe out under compression and you have some crazy wear in the tie rod of one side, that might explain the hard pull to the right phenomenon. (uneven toe out due to wear in said components) It's hard to nail down the brake distribution theory w/o some pressure transducers hooked up to the logger. (which g2x has as an option I'm pretty sure you know)

 

If one side is carrying a heavier load then there's more weight on the tire, better braking, and a pull to that side. Chassis setup 101.

Rob

 

Front lower control arm bushing (horizontal donut toward rear) bad on one side?

 

If you're correct, a car with a heavier right side should have more grip turning left than turning right. Go ahead, try convincing the NASCAR guys to put all their ballast on the right.

But thanks for the lesson.